The invention relates to an electronic cut out for a circuit to be protected, such as an amplifier circuit, as a protection against a too high a load current, wherein the load current, on exceeding a limit value, is used directly for the disconnection. This load current is converted by a suitable circuit into a proportional voltage.
Since the internal resistance of, for example, multi-stage low-frequency amplifier circuits is supposed to be very low for dynamic reasons, the load current taken out can assume inadmissibly high values in the case of ballast resistances which are too small. In order to avoid the destruction of last stage transistors by load currents which are too high, the use of fine fuses has already been proposed. The protection thus obtained however is incomplete, since the disconnection time of the fine fuses is, in general, large.